GB2052382A - A process for joining fluorinated polymer cation exchange membrane - Google Patents
A process for joining fluorinated polymer cation exchange membrane Download PDFInfo
- Publication number
- GB2052382A GB2052382A GB8004896A GB8004896A GB2052382A GB 2052382 A GB2052382 A GB 2052382A GB 8004896 A GB8004896 A GB 8004896A GB 8004896 A GB8004896 A GB 8004896A GB 2052382 A GB2052382 A GB 2052382A
- Authority
- GB
- United Kingdom
- Prior art keywords
- cation exchange
- fluorinated polymer
- exchange membrane
- membrane
- polymer film
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
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Classifications
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
- C08J5/00—Manufacture of articles or shaped materials containing macromolecular substances
- C08J5/20—Manufacture of shaped structures of ion-exchange resins
- C08J5/22—Films, membranes or diaphragms
- C08J5/2287—After-treatment
- C08J5/2293—After-treatment of fluorine-containing membranes
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B32—LAYERED PRODUCTS
- B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
- B32B27/00—Layered products comprising a layer of synthetic resin
- B32B27/06—Layered products comprising a layer of synthetic resin as the main or only constituent of a layer, which is next to another layer of the same or of a different material
- B32B27/08—Layered products comprising a layer of synthetic resin as the main or only constituent of a layer, which is next to another layer of the same or of a different material of synthetic resin
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B32—LAYERED PRODUCTS
- B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
- B32B27/00—Layered products comprising a layer of synthetic resin
- B32B27/16—Layered products comprising a layer of synthetic resin specially treated, e.g. irradiated
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B32—LAYERED PRODUCTS
- B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
- B32B38/00—Ancillary operations in connection with laminating processes
- B32B38/0008—Electrical discharge treatment, e.g. corona, plasma treatment; wave energy or particle radiation
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B32—LAYERED PRODUCTS
- B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
- B32B2305/00—Condition, form or state of the layers or laminate
- B32B2305/02—Cellular or porous
- B32B2305/026—Porous
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B32—LAYERED PRODUCTS
- B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
- B32B2307/00—Properties of the layers or laminate
- B32B2307/70—Other properties
- B32B2307/728—Hydrophilic
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B32—LAYERED PRODUCTS
- B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
- B32B2310/00—Treatment by energy or chemical effects
- B32B2310/14—Corona, ionisation, electrical discharge, plasma treatment
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
- C08J2327/00—Characterised by the use of homopolymers or copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and at least one being terminated by a halogen; Derivatives of such polymers
- C08J2327/02—Characterised by the use of homopolymers or copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and at least one being terminated by a halogen; Derivatives of such polymers not modified by chemical after-treatment
- C08J2327/12—Characterised by the use of homopolymers or copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and at least one being terminated by a halogen; Derivatives of such polymers not modified by chemical after-treatment containing fluorine atoms
- C08J2327/18—Homopolymers or copolymers of tetrafluoroethylene
Landscapes
- Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Manufacturing & Machinery (AREA)
- Materials Engineering (AREA)
- Thermal Sciences (AREA)
- Plasma & Fusion (AREA)
- Physics & Mathematics (AREA)
- Health & Medical Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Medicinal Chemistry (AREA)
- Polymers & Plastics (AREA)
- Organic Chemistry (AREA)
- Manufacture Of Macromolecular Shaped Articles (AREA)
- Separation Using Semi-Permeable Membranes (AREA)
Abstract
A method is provided for joining a fluorinated polymer cation exchange membrane, which comprises interposing a porous hydrophilic fluorinated polymer film between a fluorinated polymer cation exchange membrane containing the pendent group of -COOA (A represents H, R, NR3H or NR4, wherein R is alkyl having 1 to 20 carbon atoms) on at least one side of the membrane and a fluorinated polymer cation exchange membrane or a fluorinated polymer film, then heat- pressing them. The invention markedly increases joining strength as compared with conventional methods.
Description
SPECIFICATION
A method for joining a fluorinated polymer cation exchange membrane
The present invention relates to a method for joining a fluorinated polymer cation exchange membrane.
More specifically, the present invention relates to a method for joining a fluorinated polymer cation exchange membrane [X] containing the pendent group of -COOA on at least one side of the membrane and a fluorinated polymer cation exchange membrane [Y] orafluorinated polymer film.
Hereinabove, A represents H, R, NR3H or NR4, in which R is alkyl having 1 to 20 carbon atoms.
The joining of a cation exchange membrane is exceedingly useful in the industry. In the industrial utilization of the joining art of a cation exchange membrane, there are included, for example, formation of a cation exchange membrane in any desired shape, production of a sufficient size of the cation exchange membrane required for an industrial use when such a large size is difficult to be manufactured. It is also useful in repairing a tear or a hole of the cation exchange membrane which occasionally took place during utilization or handling. The present invention provides a joining method of a fluorinated polymer cation exchange membrane which is very much useful industrially.
The joining method of the present invention is characterized by interposing a porous hydrophilic fluorinated polymer film between a cation exchange membrane [X] containing the pendent group of -COOA on at least one side of the membrane and a cation exchange membrane [Y] or a fluorinated polymerfilm,then heat-pressing them.
Afluorinated polymer cation exchange membrane having carboxylic acid groups as the pendent group are well-known to the art as a capable membrane in a wide use and the joining art of the membrane is extremely important.
A fluorinated polymer cation exchange membrane [X] used in the present invention may contain the pendent group of carboxylic acid groups on both surfaces of the membrane, in the entirety of the membrane or the one surface of the membrane. The thickness of such carboxylic acid group layer is 1 u or more, more preferably 10 > or more.
The carboxylic acid groups include -COOH type, -COOR, -COONR3H or -COONR4, which is obtained by the treatment of -COOH group with an alcohol, a tertiary amine, a quarternarv ammonium base or a salt of the foregoings, respectively. Hereinabove, R represents alkyl having 1 to 20 carbon atoms. As these treating agents, alcohols such as methanol, ethanol, etc., tertiary amines such as triethylamine etc., quaternary ammonium bases such as tetrabutylammonium hydroxide etc., may be employed. Salts oftertiaryamines includetriethylamine hydrochloride etc., and salts of quaternary ammonium bases include tetrabutylammonium chloride etc.
A fluorinated polymer cation exchange membrane [X] is produced by polymerization of fluorocarbon monomers, or by denaturization of one or both sides of a sulfonic acid type cation exchange membrane or an ethylene diamine treated cation exchange membrane, sold by E.l. Du Pont de Nemours & Co.
Afluorocarbon polymer cation exchange membrane [Y] may be identical with the cation exchange membrane [X], or a fluorinated polymer cation exchange membrane having the pendent groups of sulfonic acid groups or sulfon amide groups, of which sulfonic acid groups or sulfon amide groups are treated with a tertiary amine, a quaternary ammonium base or a salt of the foregoings. A cation exchange membrane having the pendent group of sulfonic acids includes "Nafion" #110, #315, #415 etc., produced and sold by E.I. Du Pont de Nemours & Company. A process for treatment of a cation exchange membrane with the pendent groups of sulfonic acid groups with a quaternary ammonium base and the like is disclosed in the Japanese Patent
Publication (non-examined) No. 49394/1975.
Afluorinated polymer film includes a film of a polymer or a copolymer obtained by the polymerization of tetrafluoroethylene, 6-fluoropropylene, perfluoroalkylvinylether, 3-fluorochloroethylene and the like. For example, a copolymer of tetrafluoroethylene and 6-fluoropropylene and a polymer of 3-fluorochloroethylene have melting points of 270"C and 21 5 C, respectively, and are preferably employed in particular, since their melting points are close to those of the cation exchange membranes.
A fluorinated polymer film is, prior to the joining, subjected to hydrophilic treatment of at least, joined portion. The hydrophilic treatment is effected according to various processes, including the treatment by corona discharge. The hydrophilic treatment with activated sodium such as metallic sodium, sodium dispersion, stabilized metallic sodium and the like is also effectively employed. The treatment with a surface active agent such as perfluorocarbon surface active agents and the like is also effective. Further, the hydrophilic treatment with a titanium compound such as potassium titanate, titanium oxide and the like is also used.
A porous hydrophilic fluorinated polymerfilm includes a microporous membrane having the pendent groups of sulfonic acid groups or sulfon amide groups, of which sulfonic acid groups or sulfon amide groups are treated with a tertiary amine, a quaternary ammonium base, or a salt of the foregoings, thereby being converted to the meltprocessable membrane.
A porous fluorinated polymer film subjected to the hydrophilic treatment is also used as a porous hydrophilic fluorinated polymer film. Examples of the porous fluorinated polymer film is a porous film of polytetrafluoroethylene, which is exemplified by "GORETEX" produced by JUNKOSHA K.K.
The hydrophilic treatment is carried out by corona discharge or by the treatment with an activated sodium such as metallic sodium, sodium dispersion, stabilized metallic sodium and the like. The treatment with a surface active agent such as perfluorocarbon surface active agents, or a titanium compound such as potassium titanate, titanium oxide and the like is also effectively employed.
The joining is effected by heat-pressing. The joining with adhesives, an alkanol solution dissolv ing a low equivalent weight cation exchange membrane, and the like are also available, but heatpressing is the most effective. The heat-pressing is executed using a hot press and the like at 200 to 300"C, preferably 230 to 260"C. The pressing pressure is 2 to 150 kg/cm2, preferably 10 to 100 kg/cm2.
The pressing time is 1 to 30 min., preferably 3 to 10 min.
It is not made clear why the joining strength can be markedly improved by the interposition of a porous hydrophilic fluorinated polymer film, followed by heat-pressing, but is surmised as below. That is, heat-melted resin of the cation exchange membrane, upon heat-pressing, penetrates into perforations of the porous fluorinated polymer film, then solidify in the perforations. By such, as it were, an "anchorshaped" or"wedge-shaped" joining effect, a super iorjoining strength is provided as compared with a conventional method.
The present invention will be explained in more detail by way of examples that follow, which examples are not construed to limit the scope of the present invention.
Example 1
A carboxylic acid type cation exchange membrane, which was obtained by denaturizing both sides of a sulfonic acid type cation exchange membrane, was treated with hydrochloric acid to prepare a -COOH type membrane.
As a microporous membrane containing the pendent group of sulfonic acid groups, "Nafion" #701, produced by E.l. Du Pont de Nemours & Co, was treated with hydrochloric acid to give a -SO3H type microporous membrane. The obtained microporous membrane was further treated for 1.5 hours with a 50 % aqueous methanol solution containing 0.2 mole of tetra(n-butyl)ammonium hydroxide.
Between two pieces of so treated -COOH type cation exchange membranes, was the so treated microporous membrane sandwiched, then heatpressed for 5 min. at 250"C under the pressure of 70 kg/cm2. The resulting joined membranes were immersed in a depleted brine removed from an ion exchange membarne electrolytic cell for 2 months, but no peeling off of the joined portion was observed.
Example 2
A carboxylic acid type cation exchange membrane obtained by denaturization of one side of a sulfonic acid type cation exchange membrane was treated with hydrochloric acid, then a -COOH type cation exchange membrane [X] being obtained.
A microporous membrane containing the pendent group ofsulfonicacid groups, "Nafion" #710 was subjected to the treatment with hydrochloric acid to obtain a -SO3H type. The -SO3H type microporous membrane was then treated for 1.5 hours with a 50 % aqueous methanol solution containing 0.2 mole of tetra (n-butyl)ammonium hydroxide.
A cation exchange membrane with the pendent group of sulfonic acid groups, "Nafion" #315, produced by E.l. Du Pont de Nemours & Company was converted to a -SO3Na type membrane with sodium hydroxide. The obtained -SO3Na type membrane was then treated for 1 hour with a 50% aqueous methanol solution containing 0.2 mole of tetra(n-butyl)ammonium chloride to provide thus treated cation exchange membrane [Y].
Between the so treated cation exchange membrane [X] and the so treated cation exchange membrane [Y], the so treated microporous membrane was sandwiched, then heat-pressed for 7 min.
at 240"C under the pressure of 80 kg/cm2. The joined membranes were subjected to the immersion test for 2 months in a similar fashion to that of Example 1. No peeling off of the joined portion occurred even after 2 months.
Example 3
Both sides of a sulfonic acid type cation exchange membrane were denaturized to obtain a carboxylic acid type membrane, then treated with hydrochloric acid, thereby preparing a -COOH type membrane.
The obtained membrane was further treated for 16 hours with a 50% aqueous methanol solution containing 0.2 mole of tetra(n-butyl)ammonium hydroxide. The heat-pressing was followed similarly to that of Example 1. The resultant joined membranes were immersed for 2 months in a depleted brine exiting from an ion exchange membrane electrolytic cell, but peeling off of the joined portion was not seen.
Example 4
A carboxylic acid type exchange membrane, obtained by denaturization of both sides of a sulfonic acid type cation exchange membrane, was converted to a -COOH type membrane by the treatment with hydrochloric acid.
On the other hand, "Nafion" #701, a microporous membrane containing the pendent group of sulfonic acid groups, which was produced by E.l. Du Pont de
Nemours & Company was treated in a similar mannerto that of Example 1.
A film of copolymer of tetrafluoroethylene and 6-fluoropropylene was subjected to corona discharge on its one side.
The joined membrane and film resulted from heat-pressing at 270"C under the pressure of 70 kg/cm2 were immersed for 2 months in a depleted brine discharged from an ion exchange membrane electrolytic cell, no peeling off of the joined portion was observed.
Example 5
A carboxylic acid type cation exchange membrane was prepared by denaturizing both sides of a sulfonic acid type cation exchange membrane, then converted to a -COOH type membrane by the treatment with hydrochloric acid.
As a porous hydrophilic fluorinated polymerfilm, a film of polytetrafluoroethylene whose porous one side was subjected to corona discharge was employed.
The joined membranes heat-pressed in a similar manner to that of Example 4 were immersed for 2 months in a depleted brine removed from an electrolytic cell of an ion exchange membrane, but no peeling off took place.
Example 6
A carboxylic acid type cation exchange membrane obtained by denaturizing both sides of a sulfonic acid type cation exchange membrane was converted to a -COOH type membrane by the treatment with hydrochloric acid.
A porous film of polytetrafluoroethylene, both sides of which were treated by corona discharge was used as a porous hydrophilic fluorinated polymer film.
A film of copolymer of tetrafluoroethylene and 6-fluoropropylene was treated by corona discharge in its one side.
The membrane and the film treated above, respectively, were heat-pressed similarly to Example 4 with the interposition of the treated porous hydrophilic fluorinated polymer film. The joined membrane and film were subjected to the immersion test for 2 months in a depleted brine exiting from an ion exchange membrane electrolytic cell, but no peeling off of the joined portion was observed.
Claims (7)
1. A method for joining a fluorinated polymer cation exchange membrane, which comprises interposing a porous hydrophilicfluorinated polymer film between a fluorinated polymer cation exchange membrane [X] containing the pendent group of -COOA (A represents H, R, NR3H or NR4, wherein R is alkyl having 1 to 20 carbon atoms) on at least one side of the membrane and a fluorinated polymer cation exchange membrane [Y] or a fluorinated polymer film, then heat-pressing them.
2. The method of Claim 1, wherein said porous hydrophilic fluorinated polymer film comprises a microporous membrane containing pendent groups of sulfonic acid groups or sulfon amide groups, whose sulfonic acid groups or sulfon amide groups are treated with a tertiary amine, a quarternary ammonium base, or a salt of the foregoing amine or base.
3. The method of Claim 1, wherein said porous hydrophilicfluorinated polymer film comprises a porous hydrophilicfluorinated polymer film subjected to hydrophilic treatment by corona discharge, or with metallic sodium, sodium dispersion, stabilized metallic sodium, potassium titanate, titanium oxide or surface active agents.
4. The method of Claim 1, wherein said fluorinated polymer cation exchange membrane [Y] comprises the fluorinated polymer cation exchange membrane [Xl.
5. The method of Claim 1, wherein said fluorinated polymer cation exchange membrane [Y] comprises a fluorinated polymer cation exchange membrane containing pendent groups of sulfonic acid groups or sulfon amide groups, whose sulfonic acid groups or sulfon amide groups are treated with a tertiary amine, a quaternary ammonium base, or a salt of the foregoing amine or base.
6. The method of Claim 1, wherein said fluorinated polymer film comprises a fluorinated polymer film subjected to hydrophilic treatment by corona discharge, or with metallic sodium, sodium dispersion, stabilized metallic sodium, potassium titanate, titanium oxide or surface active agents.
7. A method for joining a fluorinated polymer cation exchange membrane substantially as described with reference to any one of the examples herein.
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP5315679A JPS55145540A (en) | 1979-04-28 | 1979-04-28 | Joining method of cation exchange membrane |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| GB2052382A true GB2052382A (en) | 1981-01-28 |
Family
ID=12934975
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| GB8004896A Withdrawn GB2052382A (en) | 1979-04-28 | 1980-02-13 | A process for joining fluorinated polymer cation exchange membrane |
Country Status (5)
| Country | Link |
|---|---|
| JP (1) | JPS55145540A (en) |
| DE (1) | DE3016339A1 (en) |
| FR (1) | FR2455064A1 (en) |
| GB (1) | GB2052382A (en) |
| IT (1) | IT1144082B (en) |
Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0185228A2 (en) * | 1984-11-30 | 1986-06-25 | Asahi Glass Company Ltd. | Multi-layered diaphragm for electrolysis |
| WO1997041168A1 (en) * | 1996-04-30 | 1997-11-06 | W.L. Gore & Associates, Inc. | Integral multi-layered ion-exchange composite membranes |
| USRE37307E1 (en) | 1994-11-14 | 2001-08-07 | W. L. Gore & Associates, Inc. | Ultra-thin integral composite membrane |
| US6613203B1 (en) | 2001-09-10 | 2003-09-02 | Gore Enterprise Holdings | Ion conducting membrane having high hardness and dimensional stability |
| US6689501B2 (en) | 2001-05-25 | 2004-02-10 | Ballard Power Systems Inc. | Composite ion exchange membrane for use in a fuel cell |
| US7125626B2 (en) | 1994-12-07 | 2006-10-24 | Japan Gore-Tex, Inc. | Ion exchange assembly for an electrochemical cell |
| US7931995B2 (en) | 1997-09-12 | 2011-04-26 | Gore Enterprise Holdings, Inc. | Solid electrolyte composite for electrochemical reaction apparatus |
Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4439292A (en) * | 1981-08-13 | 1984-03-27 | Bayer Aktiengesellschaft | Treatment of perfluorinated polymer membranes containing carboxyl groups |
| JPS58109536A (en) * | 1981-12-23 | 1983-06-29 | Toyo Soda Mfg Co Ltd | Method for bonding cation exchange membrane |
| GB2121352B (en) * | 1982-05-25 | 1986-03-19 | Chlorine Eng Corp Ltd | Bonding of cation exchange membrane |
-
1979
- 1979-04-28 JP JP5315679A patent/JPS55145540A/en active Pending
-
1980
- 1980-02-13 GB GB8004896A patent/GB2052382A/en not_active Withdrawn
- 1980-04-24 IT IT48506/80A patent/IT1144082B/en active
- 1980-04-25 FR FR8009428A patent/FR2455064A1/en not_active Withdrawn
- 1980-04-28 DE DE19803016339 patent/DE3016339A1/en not_active Withdrawn
Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0185228A2 (en) * | 1984-11-30 | 1986-06-25 | Asahi Glass Company Ltd. | Multi-layered diaphragm for electrolysis |
| EP0185228A3 (en) * | 1984-11-30 | 1986-12-30 | Asahi Glass Company Ltd. | Multi-layered diaphragm for electrolysis |
| USRE37307E1 (en) | 1994-11-14 | 2001-08-07 | W. L. Gore & Associates, Inc. | Ultra-thin integral composite membrane |
| US7125626B2 (en) | 1994-12-07 | 2006-10-24 | Japan Gore-Tex, Inc. | Ion exchange assembly for an electrochemical cell |
| WO1997041168A1 (en) * | 1996-04-30 | 1997-11-06 | W.L. Gore & Associates, Inc. | Integral multi-layered ion-exchange composite membranes |
| US7931995B2 (en) | 1997-09-12 | 2011-04-26 | Gore Enterprise Holdings, Inc. | Solid electrolyte composite for electrochemical reaction apparatus |
| US6689501B2 (en) | 2001-05-25 | 2004-02-10 | Ballard Power Systems Inc. | Composite ion exchange membrane for use in a fuel cell |
| US6613203B1 (en) | 2001-09-10 | 2003-09-02 | Gore Enterprise Holdings | Ion conducting membrane having high hardness and dimensional stability |
Also Published As
| Publication number | Publication date |
|---|---|
| IT8048506A0 (en) | 1980-04-24 |
| DE3016339A1 (en) | 1980-11-13 |
| JPS55145540A (en) | 1980-11-13 |
| FR2455064A1 (en) | 1980-11-21 |
| IT1144082B (en) | 1986-10-29 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| WAP | Application withdrawn, taken to be withdrawn or refused ** after publication under section 16(1) |